Table 1.

Summary of ways and examples to improve the bioavailability of BBR.

Methods	Examples	Effect	References
Alternative delivery system	Dendrimer encapsulated and conjugated delivery of BBR	Improved BBR oral bioavailability	[9]
	Clear anhydrous reverse micelles containing amorphous BBR nanoparticles	Enhanced the hypoglycemic effect	[10]
	BBR nanosuspension	Improved lipid metabolism, lowered blood sugar	[11]
	Selenium-coated nanostructured lipid carriers	Increased intestinal absorption, improved the hypoglycemic effect	[12]
	Polymer-lipid hybrid nanoparticles loaded with BBR-phospholipid complex	Enhanced the oral efficiency, improved sustained release	[13]
	BBR-loaded solid lipid nanoparticles	Strengthened intestinal absorption, enhanced the antidiabetic effect	[14]
	A novel BBR-loaded cremochylomicron	Improved BBR oral bioavailability	[15]
Chemical structure modification	The mannose modified BBR derivative	Increased antidiabetic activity	[16]
	Synthesis of disaccharide modified BBR derivatives		[17]
	BBR derivative: nandinine	Inhibited inflammation, attenuated IR	[18]
	BBR derivative: dihydroberberine	Enhanced insulin sensitivity, attenuated IR	[19]
	9-O (lipophilic group substituted) BBR derivatives	Increased hypoglycemic activity	[20]
	C-9 modified BBR derivatives	Improved lipid-lowering activity	[21]
Coadministration with P-gp inhibitors	Tetrandrine	Decreased the efflux rate of BBR, promoted intestinal absorption	[22]
	D-α-tocopheryl polyethylene glycol 1000 succinate (TPGS)		[23]
	Glycine (GLY)		[24]
	Cyclosporine A (CsA)		[25]
	Oligomeric proanthocyanidins (OPCs)		[26]